In this study, the role of collaboration in design is discussed, placing emphasis on how to include end-users in the development process. The study is based on a literature review focusing on aspects of collaboration in design, usability and human factors. Thereby, it introduces, compares and contrasts the characteristics of both collaborative and user-centered design perspectives, leading to the collaborative-participatory design approach. Finally, the advantages, disadvantages and precautions of implementing collaborative and participatory models are pointed out.